Coming from the BVI you can do C&I in Cruz Bay St John or Charlotte Amalie St Thomas. If you’re US Citizens on a US flagged vessel you dont have to clear out of the USVI, but you have to clear into the BVI
By private vessel or bareboat you can do it on the ROAM App on your smartphone. The boat needs a customs decal.
Last week we had one of Captain Jays/ CYOA 45 Mono's out and used the ROAM App passing Johnson Reef. At Stevens the App still indicated "Processing". We changed our course and grabbed a Ball at Lind Point, reported to C&I and while we were waiting our turn it Indicated "Accepted". Lesson learned, Sometimes the app's on Island Time :-)
The ROAM app uses your phone location to determine if you are within US waters. It will almost immediately reject your submittal, as I found out, if you are even just slightly in BVI waters. Heading from the BVI to St John, submit your arrival request as soon as you enter USVI waters even if you're on the east end of St John (especially if you're not otherwise looking to visit Cruz Bay that day).
The first time in November 2018 and no luck. We were at watermelon cay St. John and it just failed to work. Was able to submit but got hung up in processing. I think it was a connectivity issue. I got a reply 5 days later when I was back in Pennsylvania that we were declined.
The second time was in January of 2019. We submitted as we were sailing back from Jost. We were initially declined due to being outside US waters. Then we resubmitted as we were passing Trunk Bay and we were cleared after about 5 minutes. No interview needed. It was amazing. We didn’t have to dinghy around to Cruz bay.